Many organisms are sensitive to electrical charge, including types of spiders that use it to fly to distant locations. It’s possible that plants may use it as a signal of coming rain intensity?

I have noticed something quite interesting: in my nursery, actual rain stimulates germination, leaf formation, flowering, and budding in a way that collected rainwater applied over identical timeframes in identical quantities using sprinklers that approximate rain drop physics fails to do. Well-water performs roughly the same as collected rainwater.

I’m speculating that there is some other signal present with actual rain that is lacking in the surrogate process. It could easily be electrical charge.